A gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section and an exhaust section. In operation, air enters an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section through a hot gas path defined within the turbine section and then exhausted from the turbine section via the exhaust section.
In particular configurations, the turbine section includes, in serial flow order, a high pressure (HP) turbine and a low pressure (LP) turbine. The HP turbine and the LP turbine each include various rotatable turbine components such as rows of turbine rotor blades and rotor disks, and various stationary turbine components such as rows of stator vanes or nozzles and turbine shrouds. The rotatable and the stationary turbine components at least partially define the hot gas path through the turbine section.
Each turbine shroud forms a ring around or circumscribes a corresponding row of the turbine rotor blades. Radial gaps are defined between blade tips of the row of turbine rotor blades and a hot side surface of each of the turbine shrouds. The gaps are generally sized to avoid rubbing of the blade tips against the hot side surface while reducing or preventing leakage of the combustion gases flowing through the hot gas path through the gap, thereby improving overall efficiency of the gas turbine engine.
Rubbing of the blade tips against the turbine shrouds may be caused by various factors. For example, rubbing may be caused by pressure pulses of the combustion gases flowing through the hot gas path and/or by thermal transients within the turbine section during startup or transitions between operating modes of the gas turbine engine. Blade strikes may potentially affect the mechanical life of the turbine rotor blades and/or potentially result in undesirable leakage of the combustion gases through the radial gaps.
Conventionally, the turbine shrouds are rigidly mounted to a static structure or portion of the turbine of gas turbine engine and are radially fixed in position during operation. As a result, the turbine shrouds do not move radially when the turbine rotor blades strike or rub the hot side surface, thus potentially resulting in bending of the turbine rotor blades and/or damage to turbine shrouds. Accordingly, a system for mounting or supporting the turbine shrouds which allows for radial movement of the turbine shroud during a blade rub or strike event, thus preventing or reducing damage to at least one of the turbine rotor blades and/or the turbine shroud, would be welcomed in the technology.